fidelity

SMART Vocabulary: related words and phrases

Disloyalty, betrayal & treason
adulterous
backstabber
betrayal
betrayer
break ranksidiom
chicane
deserter
desertion
faithless
faithlessly
faithlessness
false
fifth column
stab someone in the backidiom
tergiversation
throw someone to the lionsidiom
throw someone under the busidiom
traitor
treasonable
unfaithfulness

You can also find related words, phrases, and synonyms in the topics:

Relationships: infidelity

infidelity | American Dictionary

infidelity
noun[ C/U ]
us/ˌɪn·fəˈdel·ɪ·t̬i/
the act of having sex with someone who is not your husband or wife